package com.wonders.ghy.juc.生产者消费者;

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

class ShareData{
    private int number = 0;
    private Lock lock = new ReentrantLock();
    private Condition condition = lock.newCondition();
    public void increment() throws Exception{
        lock.lock();
        try {
            // 1判断
            while (number !=0){
                condition.await();
            }
            number++;
            System.out.println(Thread.currentThread().getName()+ number);
            condition.signalAll();
        }catch (Exception e){

        }finally {
            lock.unlock();
        }

    }

    public void decrement() throws Exception{
        lock.lock();
        try{
            // 1判断
            while (number ==0){
                condition.await();
            }
            number--;
            System.out.println(Thread.currentThread().getName() + number);
            condition.signalAll();
        }catch (Exception e){

        }finally {
            lock.unlock();
        }

    }
}

/**
 * 题目：一个初始值为0的变量，两个线程对其交替操作，一个加1一个减1，来5轮
 * 1 线程     操作      资源类
 * 2 判断     干活      通知
 * 3 防止虚假唤醒
 */
public class ProdConsumer_TraditionDemo {
    public static void main(String[] args) {
        ShareData shareData = new ShareData();
            new Thread(()->{
                for (int i = 0; i < 5; i++) {
                    try {
                        shareData.decrement();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }

            },"AA").start();
            new Thread(()->{
                for (int i = 0; i < 5; i++) {
                    try {
                        shareData.increment();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }

            },"BB").start();

        new Thread(()->{
            for (int i = 0; i < 5; i++) {
                try {
                    shareData.decrement();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }

        },"CC").start();
        new Thread(()->{
            for (int i = 0; i < 5; i++) {
                try {
                    shareData.increment();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }

        },"DD").start();

    }


}
